Recently, a thermal transfer system has been developed in which prints can be obtained from images electronically formed with a color video camera. According to one method of obtaining such prints, an electronic image is first subjected to color separation with a color filter. Then, the respective color-separated pixels are converted into electric signals. Subsequently, these signals are processed to provide yellow, magenta and cyan electric signals. Next, these signals are transmitted to a thermal printer. For obtaining prints, an yellow, magenta or cyan dye-providing element is attached to a color image-receiving element with the surfaces of the two facing to each other. Subsequently, the two elements are inserted between a thermal head and a platen roller. Using a line-type thermal head, the two elements are heated from the back surface of the dye-providing element. The thermal head has many heating means so that the dye-providing element is successively heated in response to the yellow, magenta and cyan signals therein. Subsequently, the step is repeated for the other two remaining colors. Accordingly, a color hard copy corresponding to the original image as seen on the screen is obtained.
Another method of thermally obtaining prints with the above-mentioned electric signals is a method using a laser in place of the thermal head. A dye-providing element to be used in the laser system contains a material which strongly absorbs laser rays applied thereto. Where laser rays are irradiated upon such a dye-providing element, the absorbing material acts to convert the light energy to heat energy, whereupon the heat is transmitted to the nearest dye, and the dye is then heated up to the thermal transferring temperature so as to be transferred to the adjacent image-receiving element. The absorbing material exists as a layer beneath the transferring dye and/or is blended with the dye. The irradiating laser beams are modulated by the electric signals to express the shape and the color of the original image. As a result, only the dyes within the irradiated areas on the dye-providing element are heated and thermally transferred.
As mentioned above, direct contact of a dye-providing element to an image-receiving element is indispensable in a thermal transfer recording system, and, after recording, the two elements must be peeled off from each other.
However, these methods were not without their problems. For example, during the peeling step, the elements are statically charged and, as a result, dust adheres to them so that the recorded surface is undesirably stained. Also, where recorded image-receiving elements are stacked up, they would attach to each other due to static electricity and heat so that they could not be separated from each other. As the case may be, the dye providing layer would peel off to adhere to the image-receiving element. Thus, the statically charged dye-providing element would often be wrinkled. Additionally, discharge of the accumulated static charges would have an adverse effect on the electric system of recording apparatus. These problems prevent implementation of the thermal transfer recording system described above. In addition, these problems often diminish the quality of the recorded images.
The invention as disclosed in JP-A-61-199997 (the term "JP-A" as used herein means an "unexamined published Japanese patent application") is one attempt to solve these problems, but is not satisfactory.